Bending machine



Nov. 4, 1941 J. HOLLFELDER 2,261,763

BENDING MACHINE Filed Aug. 19, 1940 4 Sheets-Sheet 1 JOHN HOLL FE LDER ATTORNEY-S Nov. 4, 1941. J. HOLLFELDER 2,261,763.

BENDING MACHINE Filed Aug. 19, 1940 4 Sheets-Shet 2 JOHN Hop; F540; R

ATTORNEYS Nov. 4, 1941. J. HOLLFELDER BENDING MACHINE 4 Sheets-Sheet 5 Filed Aug. 19, 1940 Jomv HOLLFELDER ATTORNE Y5 Nov. 4, 1941. J. HOLLFELDER BENDING MACHINE 4 Sheets-Sheet 4 Filed Aug. 19, 1940 INVENTOR. JbHN Hour-51.05 R

A TTORNBG Patented Nov. 4, 1941 UNITED STATES P TENT OFFICE This invention relates to metal bending, cutting, stamping and like machines and, more particularly, to a fluid operating means therefor.

In the past, the actuating mechanism of such machines comprised heavy and costly gearing or a fluid actuating mechanism which was complicated and required a very high fluid pressure.

An object of this invention is to provide a metal bending, cutting, stamping or like machine with a fluid pressure actuating mechanism which requires low pressure.

Another object of the present invention is to provide a simple and inexpensive actuating mechanism for a metal bending or like machine.

A still further object of the invention is to provide a machine of this character in which the actuating mechanism is durable and which will readily carry out the work for which it is designed.

Other objects of the invention will become apparent in the course of the following specification.

The above and other objects of the present invention are accomplished by providing a metal bending, stamping, cutting or like machine having a frame with a stationary die thereon and a movable die cooperating with said lower die and guided between guides on said frame, said movable die having a fluid pressure (such as compressed air) actuating means comprising an actuating plate resting on a diaphragm of resilient material, preferably rubber, the actuating plate being raised and lowered when fluid pressure is admitted and released from a chamber beneath the diaphragm, the actuating plate having levers connected thereto which are normally out of engagement with arms on the mov able die but which may be brought into engagement with said arms to move the movable die away from the stationary die when fluid pressure is applied to the diaphragm, so that the metal to be bent, cut or stamped may be positioned over the bottom die, the movable die being returned when the pressure is released. The actuating plate also has pressure applying levers thereon which levers are adapted to engage the movable die arms when the flrstmentioned levers are not in engagement with them and press the movable die against the metal to be bent, cut or stamped when fluid pressure is applied to the diaphragm.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawings,

showing by way of example a preferred embodiment of the invention.

In the drawings:

Figure 1 is a front elevational view, the machine being shown in its normal inoperative position;

Figure 2 is a view similar to Figure 1, the movable die being shown positioned away from the stationary die, the fluid pressure operating means being shown inflated;

Figure 3 is a front elevational view, showing the position of the various parts of the machine during the bending, cutting or stamping operation;

Figure 4 is a sectional view taken on the line 44 of Figure 1; l

Figure 4a is an enlarged View of left-hand corner of Figure 4; and

Figure 5 is an end elevational view of the machine taken on the line 5-5 of Figure 1.

Like numerals refer to like parts throughout the several views.

The machine of this invention comprises a bottom plate Ill rectangular in shape, having a raised border Illa around the same.

A rectangular sheet of resilient material l5, preferably rubber, substantially the same size as the bottom plate, is placed over the bottom the lower plate ill, the outer edges of said sheet I5 cover- 3 ing the border Illa. Channel members H and I2 are'mounted along the sides of th plate- It) over the sheet l5 and on the border Illa, bolts l6 passing through the bottom of the channel members H and I2, through the sheet l5 and into the border Illa. End channel members l3 and I4 are mounted across the opposite ends of the bottom plate In over the sheet I5 and on the border Illa, bolts 11 passing through the bottom of channel members l3 and I4, through the sheet l5, and into the border Illa.

The bolts l6 and I! are drawn tightly so that theedges of the sheet l5 are held tightly between the bottoms of the channel members ll, l2, l3 and I4 and the border Illa, forming a fluid-tight chamber l8 below the sheet l5.

An actuating plate l9, substantially co-extensive with the enclosure formed by the channel members H, l2, l3 and I4, rests on top of the sheet l5. A lining sheet 20 of soft, pliable resilient material, preferable rubber, substantially the same size as the bottom of the actuating plate is fastened to the said bottom to prevent chafing between the sheet l5 and the actuating plate and to prevent the sheet I 5 from becoming IQ and contact with the moving, end-mechanisms ofv the machine.

Parallel longitudinally extending framepieces- 29 and 39 extend between the supports 2| and 22. and have a space 3| therebetween substantially centrally between the top and bottom of the upright supports 2| and 22.

A table 32 is mounted on top of the parallel frame pieces 29 and 39 and has mounted thereon a longitudinally extending stationary die 33.

Mounted for vertical movement above the stationary die 33 is a movable die 34, extending longitudinally between the supports 2| and 22', having a projection 35 extending through the space 23 in the support 2| and projecting beyond said support and guided in its up and down vertical movement by guide plates 36 and 31 on opposite sides of the space 23. Likewise, the movable die 34 has a projection 38 on the opposite end thereof, said projection extending through the space 24 and beyond the support 22 and is guided in its vertical movement by guide plates 39 and 49 mounted on the support 22 on opposite sides of the space 24.

The movable die-34 has backing. plates. 4| and 42 on opposite sidesthereof heldin position by bolts 43;

Pivotally mounted on the projections 35 and 38, respectively, and projecting downwardly therefrom are actuating bars 44 and. 45; The bar 44 has a rectangular shaped aperture 46 therein and a semi-circular shaped surface 41 on the lowermost end thereof, while the bar 45 has a rectangular shapedaperture 41 therein and a semi-circular shaped surface 48 on the lower end thereof.

Rotatably mounted on the. frame piece 29 on opposite ends thereof are wheels 49 and 59. A longitudinally slidable rod |.mounted in guides 52 and 53 is pivotally connected at one end to the top of the wheel 59 at 5|a, while the opposite end thereof is pivotally connected to a link 54 which, in turn, is pivotally connected at 55 to the wheel 49.

Pivotally connected on the top of the wheel 49 and extending through the upright support 2| and slidably supported in an aperture 56 in said support is a shifting lever 51 having an enlarged head 58 adapted to engageathe arm 44. On the top of the wheel 59, is pivotally connected at 5|a a shifting lever 59 having anenlarged head 69 adapted to engage the arm 45. The lever 59 is slidably supported in an-aperture 6| in the upright 22.

A crank 62 is connected to the Wheel 59, the crank in turn having pivotally fastened to the end thereof at 63 a lever 64, the opposite end of which is pivoted at 65 to a pedal 66 pivoted at 61 to the base of the machine. The pedal 66 is adapted to be lowered against the tension of the spring 68, onev end of which is fastened to the channel member II and the other end connected to the pedal.

Mounted on opposite sides of the actuating plate l9 in substantially the center thereof are upwardly extending bars 69 and 69a, having cross-arms 19 and 19a fixedly mounted thereon. A link 1| is pivotally mounted at 1| a to one end of the cross-arm 19, the link being pivotally connected to another link 1.2 which is pivotally connected to a short link 13, in turn, connected to one end of a crank 14. The crank 14 is pivoted at 15 in substantially the center thereof to the upright 2|, the opposite end of the crank having an arm 16 therein extending outwardly beyond the upright 2|. The links 1| and 12 are adjustable in respect to one another by means of the adjustment holes 11.

The opposite end of the upright 19 is connected to a crank 18 pivotally mounted at 19 on the upright 22; said connection being through a link 89, one end of which is pivotally connected to the cross-bar 19 and the opposite end pivotally connected to a link 8|, said links being adjustable in relation to oneanother through the adjustment holes 82 therein. The opposite end of the link 8| is connected-to a short link 83 pivotally connected to the upper part of the crank 18.

The lower end of the crank 18 has an outwardly extending arm'84 secured thereto, which extends beyond the upright 22.

The link system above described is duplicated on the opposite side of the machine connecting one end of the cross-arm 19a to a crank pivotally mounted in the upright 2| adjacent the crank 14 and similar thereto. A roller 85 is rotatably mounted between the arm 16 and alike arm-on the crank on the opposite side. Likewise, the opposite end of the cross-arm 19a is connected through links similar to links on the opposite side of the machine, as above described, to: a crank 18a pivotally mounted in the upright 22 adjacent the crank 18 and similar thereto, there being a roller 86 rotatably mounted between the arm 84 and a similar adjacent arm 84a on the opposite side of the machine, which arm is $6- cured to the aforementioned crank 18a.

The link 89 and the similar link on the opposite side of the machine are adapted to engage in their upward movement idler rollers I99 on opposite sides of the machine. The link 1| and the link similar thereto on the opposite side of the machine are adapted to respectively engage in their upward movement the idler rollers |9| and |9|a.

Pivotally mounted at 81 in a slot 88 on the top of the actuating plate I9 is a pressure lever 89 which extends diagonally upwardly from the top of said plate through the space 23 in the upright 2| and through the rectangular aperture 46 in the bar 44, the end of the lever 89 being hooked at 99 to engage the bottom of the aperture 46.

Intermediate its ends the pressure lever 89 is pivoted on the pivot 9| to the frame pieces 29 and 39.

In a slot 92 on the top of'the actuating plate I9 is pivotally mounted at 93 another pressure lever designated by the reference numeral 94, which lever extends diagonally upwardly from the top of the plate through the space 24 in the upright 22 and through the rectangular aperture 41 in the bar 45. The end of the lever 94 is hooked at 95 to engage the bottom of the aperture 41. Intermediate its length the lever 94 is pivoted at I92 to the fram pieces 29 and 39.

A fluid inlet pipe line 96 leads from a fluid supply source and is connected to the chamber I8. The inlet pipe line 96 has a control valve 91 therein.

An exhaust pipe line 98 having a fluid release valve 99 therein is likewise connected to the chamber I8.

The normal inoperative position of the various parts of the machine of this invention is illustrated in Figure 1 of the drawings. When it is desired to operate this machine to bend, cut, or stamp a sheet of metal, the upper die 34 must be moved away from the lower die 33, so that the metal may be placed therebetween.

It will be readily understood that cutting or stamping dies may be substituted for the bending dies 33 and 34 illustrated in the drawings.

To raise the upper die 34, it is necessary for the operator to first step on the foot pedal 66, which moves the lever 64 and the crank 62 downwardly, turning the wheel 59 in a counter-clockwise direction. The turning of the wheel 59 in a counter-clockwise direction slides the rod to th left, as shown in Figure 1 of the drawings, whichthrough the link 54 turns the wheel 49 in a clockwis direction, sliding the shifting lever 51 to the right, causing the arm 44 to swing outwardly to the dotted position shown in Figure 1 of the drawings. Likewise the counterclockwise movement of the wheel 59 slides the shifting lever 59 to the left, causing the arm 45 to swing outwardly to the position shown in dotted lines in Figure 1. In this position, the bottom of the aperture 46 in th arm 44 is out of the path of the hooked portion 99 of the pressure lever 89, as is th bottom of the aperture 41 of the arm 45 out of the path of the hooked portion 95 of the pressure lever 94. The arms 44 and 45 may move upwardly and the hooked portions 99 and 95 move downwardly without the hooked portions and arms contacting one an other.

The operator retains his foot on the foot pedal 66 and admits fluid pressure into the chamber F8 beneath the diaphragm I5 by turning the control valve 91, allowing the fluid pressure to enter from the source through the inlet pipe 96. As the chamber I8 becomes filled with the fluid, the rubber diaphragm I5 is caused to move upwardly, which causes th actuating plate I9 also to move upwardly. Upward movement of the actuating plate I9 moves th cross-arm I8 and 19a upward causing the links II and 80 to engage the idling rollers I9I and I09, respectively, which will cause the crank I4 and the arm I6, which is secured thereto, to move in a counter-clockwise direction around the pivot I5 until the roller 95 engages the semi-circular surface 41 on the lowermost end of the arm 44. Simultaneously therewith, the crank I8 is moved in a clockwise direction around the pivot I9, which raises the arm 84, bringing the roller 88 into contact with the semi-circular surface 48 on the lowermost end of the arm 45.

-When the rollers 85 and 86 engage the ends of the arms 44 and 45, respectively, foot pressure is released from the pedal 66, the spring 68 returning the shifting lever mechanism to its normal position. Further fluid pressure admitted to the chamber I8 will raise the upper die to the position shown in Figure 2 of the drawings.

Th admission of fluid pressure beneath the diaphragm I5 causes the lining sheet 29, which is of a soft, pliable resilient material, to spread, which fills in any gap existing between the sides and ends of the actuating plate I9 and the channel members II, I2," I3 and I4, as shown at I03 in Figures 2 and 3 of the drawings. This prevents the rubber diaphragm I5 from becoming pinched between the channel members and the actuating plate.

When the upper die 34 has been moved upwardly to the desired position, fluid pressure from the source is cut oif by shutting the valve 91, which will maintain the pressure beneath the actuating diaphragm I5 holding the actuating plate against further movement. The metal to be bent is then positioned between the top die 34 and the bottom die 33. The fluid pressure is then released from the chamber I8 by opening the release valve 99 and allowing the pressure to exhaust from the chamber I8 through the exhaust pipe line 98. As the pressure is exhausted from the chamber I8, the diaphragm I5 and the actuating plate I9 on top thereof moves downwardly. Downward movement of the actuating plate I9 causes the cross arms I9 and 10a to move downwardly, the links II, I2 and I3 moving the crank I4 and arm I6, which is secured thereto, in a clockwise direction around the pivot I5, lowering the roller 85. Simultaneously therewith the crank I8 is moved in a counter-clockwise direction around the pivot I9 through the links 89, 8|, 83, lowering the roller 86.

As the rollers and 86 are lowered, the movable upper die 34 is lowered by gravity, since the arms 44 and 45 pivoted to opposite ends of the die 34 are in engagement with the rollers 84 and 85, respectively. The arms 44 and 45 remain in contact with the rollers 84 and 85 until the upper die 34 engages the metal to be bent, which was placed over the lower die 33 when the upper die 34 was in its uppermost position, as above described, the upper die coming to rest on the metal. Further downward movement of the rollers 85 and 88 causes the arms, 44 and 45 to become disengaged therefrom and swing inwardly to the position shown in full lines in Figure 1 of the drawings. In this position the upper die 34 is resting on the metal to be bent, the metal being over the lower die 33. I

To bend the material, fluid pressure is again admitted to the chamber I8, causing the actuating plate I9 to rise. The pressurelever 89, by the raising of the actuating plate I9, is pivoted in a clockwise direction about the pivot 9|, the pressure lever 94 being pivoted in a counterclockwise direction about the pivot 93. Since the arms 44 and 45 are now in the line of movement of the pressure of levers 89 and 94, the hooked portion 99 on the lever 89 engages the bottom of the aperture 46 in the arm 44, while the hooked portion 95 on the pressure lever 94 engages the bottom of the aperture 41 in the arm 45. Further upward movement of the actuating plate I9 will cause the arms 44 and 45 to move downwardly and thereby cause the upper die 34 to be pressed against the material over the bottom .die 33, bending the material. The position of the parts of the machine during the bending operation is shown in Figure 3 of the drawings.

Fluid pressure from the chamber I8 is then released through the exhaust pipe line 98 by opening the release valve 99, returning the machine to its inoperative position, as shown in Figure 1 of the drawings.

It is apparent that the specific illustrations shown have been given by way of illustration and not by way of limitation and that the structure above described is subject to a wide variation and modification without departing from the scope or intent of the invention, all of which variations and modifications are to be included within the scope of the present invention.

What is claimed is:

1. In a machine of the class described having a frame, a fixed die mounted on said frame, a movable die cooperating with said fixed die, a fluid pressure actuating mechanism for actuating said. movable die comprising a diaphragm of resilient material mounted over a base in fluidtight relation thereto and adapted to be inflated and deflated by means of fluid pressure, actuating means removably connected to said mov able die, said actuating means being actuated by said diaphragm when the same is' inflated to move said movable die away from said fixed die under fluid pressure and actuated when the diaphragm is deflated to permit said movable die to return to said fixed die, and pressure exerting means connected to said actuating means and adapted to be connected with said movable die when said actuating means is disconnected therefrom so that fluid pressure on said'diaphragm will cause said pressure exerting means to move the movable die toward the fixed die under fluid pressure.

2. In a machine of the class described having a frame, a fixed die mounted on said frame, a movable die cooperating with said fixed die, a fluid pressure actuating mechanism for'actuating said movable die comprising a diaphragm of resilient material mounted over a base in fluidtight relation thereto and adapted to be inflated and deflated by means of fluid pressure, actuating meansactuated by said diaphragm when the same is inflated, connecting means pivotally mounted on said movable die and adapted to be removably connected with said actuating means to move the movable die by fluid pressure away from said fixed die and to permit said movable die to return to said fixed die by gravity when the diaphragm is deflated; and pressure exerting means connected to said actuating means and adapted to be connected with said movable die when said connecting means is disconnected therefrom, whereby fluid pressure on said diaphragm will cause said actuating means'and the pressure exerting means to move the movable die toward the fixed die under fluid pressure.

3. In a machine of the class described having a frame, a fixed die mounted on said frame, a movable die cooperating with said fixed die, arms pivotally mounted on opposite endsof said movable die, a diaphragm comprising a sheetof rubber mounted over a base on said frame in fluidtight relation thereto and adapted to be inflated and deflated by means of fluid pressure, an actuating plate actuated by said diaphragm when the same is inflated and deflated, connecting means operable by said diaphragm, means forbringing said arms into connection with said connecting means to move said movable die away from said fixed die when said diaphragm is inflated and to permit said movable die to return to said fixed die by gravity when the diaphragm is deflated, and pressure exerting meansoperablebysaidactuating plate and adapted to engage said arms when said connecting means is disconnected therefrom, whereby fluid pressure on said diaphragm will cause said actuating plate and pressure exerting means to move the movable die toward the fixed die under fluid pressure.

4. In a bending machine having a base, a frame mounted on said base, a fixed die mounted on said frame, a movable die cooperating with said fixed die, guides on said frame guiding said movable die, arms pivotally mounted on opposite ends of said movable die, a chamber in said base, 2. diaphragm comprising a sheet of resilient material mountedover said chamber in fluid-tight relation thereto, and adapted to be inflated and deflated by means of fluid pressure, an actuating plate actuated by said diaphragm when the same is inflated and deflated, connecting means operable by said diaphragm, means for bringing said arms into connection with said connecting means to move said movable die away from said fixed die when said diaphragm is inflated and to permit said movable die to return to said fixed die by gravity when the diaphragm is deflated, and pressure exerting means operable by said actuating plate and adapted to engage said arms when said connecting means is disconnected therefrom, whereby fluid pressure on said diaphragm will cause said actuating plate and pressure exerting means to move the movable die toward the fixed die under fluid pressure.

5. In a bending machine having a base, a frame mounted on said base, a fixed die mounted on said frame, a movable die cooperating with said fixed die, arms pivoted on opposite ends of said movable die, a chamber in said base, a diaphragm comprising a sheet of resilient material mounted over said chamber in fluid-tight relation thereto and adapted to be inflated and deflated by means of fluid pressure, an actuating plate actuated by said diaphragm when the same is inflated and deflated, cranks pivotally mounted on said frame adjacent the opposite ends thereof each of said cranks being adapted to engage one of said pivoted arms, links connecting said cranks to said actuating plate, means for bringing said arms into engagement with said cranks whereby said movable die may be moved away from said fixed die when said diaphragm is inflated and to permit said movable die to return to said fixed die by gravity when the diaphragm is deflated, and pressure exerting means operable by said actuating plate and adapted to engage said arms when said cranks are not in engagement therewith, whereby fluid pressure on said diaphragm will cause said actuating plate and pressure exerting means tomove the movable die toward the fixed die under fluid pressure.

6. In a bending machine having a base, a

1 frame mounted on said base, a fixed die mounted on said frame, a movable die cooperating with said fixed die, arms pivoted on opposite ends of said movable die, a chamber in said base, a diaphragm comprising a sheet of rubber mounted over said chamber in fluid-tight relation thereto, and adapted to be inflated and deflated by means of fluid pressure, an actuating plate actuated by said diaphragm when the same is inflated and deflated, cranks pivotally mounted on said frame adjacent the opposite ends thereof each of said cranks being adapted to engage one of said pivoted arms, links connecting said cranks to said actuating plate, shifting'levers adapted to engage said pivoted arms and bring the same into the path of movement of said cranks whereby said movable die may be moved away from said fixed die when said diaphragm is inflated and returned to said fixed die by ravity when the diaphragm is deflated, and pressure exerting means operable by said actuating plate and adapted to engage said arms when said cranks are not in engagement therewith, whereby fluid pressure on said diaphragm will cause said actuating plate and pressure exerting means to move the movable die toward thefixed die under fluid pressure.

'7. In a bending machine having a base, a frame mounted on said base, a fixed die mounted on said frame, a movable die cooperating with said fixed die, arms pivoted on opposite ends of said movable die, a chamber in said base, a diaphragm actuating plate, shifting levers adapted to engage 15 said pivoted arms and bring the same into the path of movement of said cranks, whereby said movable die may be moved away from said fixed die when said diaphragm is inflated and returned to said fixed die by gravity when the diaphragm is deflated, pressure exerting levers each pivoted intermediate its length to said frame and connected at one end to said actuating plate the opposite ends being adapted to engage said pivoted arms when said cranks are not in engagement therewith whereby fluid pressure on said diaphragm will cause said actuating plate and pressure exerting means to move the movable die toward the fixed die under fluid pressure.

JOHN HOLLFELDER. 

